量子失谐几何度量的紧致下界
量子物理
2015-05-20 v3
摘要
Dakic、Vedral 和 Brukner [Physical Review Letters \tf{105},190502 (2010)] 给出了两体量子态中量子失谐的几何度量，定义为该态到最近经典量子（或零失谐）态的距离，并推导出了两量子比特态的显式公式。此外，S. Luo 和 S. Fu [Physical Review A \tf{82}, 034302 (2010)] 得到了该几何度量对于一般两体态的通用形式，并建立了一个下界。在本篇简短报告中，我们得到了一个一般两体态中量子失谐几何度量的严格下界，该下界优于 S. Luo 和 S. Fu 所得到的下界。
引用
@article{arxiv.1010.1920,
title = {Tight lower bound to the geometric measure of quantum discord},
author = {Ali Saif M. Hassan and Behzad Lari and Pramod S. Joag},
journal= {arXiv preprint arXiv:1010.1920},
year = {2015}
}
备注
10 pages,2 figures. In the previous versions, a constraint was ignored while optimizing the second term in Eq.(5), in which case, only a lower bound on the geometric discord can be obtained. The title is also consequently changed. Accepted in Phys.Rev.A